Description: (Applicant's Description) The Gene Expression Core represents a new Core facility for the UCCC and is most likely one of the first such cores to be peer-reviewed in the CCSG system. This facility is dedicated to making molecular gene expression technology available in a user-friendly manner. We utilize oligonucleotide arrays, cDNA arrays and quantitative RNA methodologies to investigate the changes in gene expression for our users. Affymetrix technology is used for the oligonucleotide arrays. These arrays are capable of analyzing human, mouse, rat and yeast species. Expressed sequence tag (EST) arrays of the mammalian species are available for gene discovery purposes. Custom cDNA arrays are constructed from sequence-verified clones. Quantitation of selected genes is made possible using real time PCR. With these capabilities, the objectives of the Gene Expression Core facility are to: 1) Analyze gene expression using both oligonucleotide and cDNA arrays; 2) Facilitate gene discovery with the inclusion of expressed sequence tag (EST) capability to the arrays; 3) Accurately quantitate gene expression using real time PCR; 4) Provide support for data analysis and bioinformatics by our data mining tool and our cluster analysis capabilities; 5) This facility has a commitment to utilizing a variety of approaches for expression analysis. This core was established in response to the technological advances in gene array, as well as the demand for high throughput expression analysis to investigate pathogenesis, therapeutics, genetic susceptibility and gene discovery in cancer research. The informatics aspect is of paramount importance, and three distinct analysis programs as well as a network are used to store and analyze the data. The facility has the capability and flexibility to adapt as the field of array technology changes. These changes are translated into upgrading the facility and its services. More complex analysis of gene expression arrays is available to members through the Biostatistics/Bioinformatics Core.